- Persons with a history of intracranial bleeding at any time, a tumor or blood vessel abnormality in the brain and/or spinal cord at any time, a history of surgery involving the brain or spinal cord within the last 5 years, or a history of bleeding from the gastrointestinal tract (eg, esophagus, stomach, colon, rectum) within the last 6 months or a major surgery within the last 30 days.